Discharge valve



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. H. W. WESHART ET AL DISCHARGE VALVE Filed June 21, L925 W 2' )2 7m Wis/7a):

HAROLD w. wrsnanr WILLI wrsnan'r, or oLINroN, IOWA, ASSIGNORS 'ro CLIMAX ENGINEERING com any, or CLINTON, IOWA. A CORPORATION or minaw.

msonanen' VALVE.

Application filed June 21, 1926. Serial No. 117,530.

This invention relates to discharge valves, with particular reference to valves adapted to be used with submerged typerotary compressors wherein there is a possibility of entry of liquid to the pump during idle periods.

It is therefore an object of this invention to provide an improved form of discharge valve for gas or air compressors adapted to provide abnormal valve lift in the event of liquid being entrained in the compressor, as when starting up there is likely to be some liquid and oil in the pump, overloading the driving mechanism in forcing the liquid out through the valve.

It is also an object of this invention to provide animproved valve for rotary compressors submerged in a'liquid in order to prevent unnecessary mixing of the compressed gas with the liquid.

' Other and further important objects of this invention will be apparent from the dis closures in the specification and the accompanying drawings.

This invention (in a preferred form) is illustrated in the drawings and hereinafter more fully described. 7

On the drawings:

Figure 1 is a fragmentary section with parts broken away to show the application of a valve embod ing the features of this invention to the side plate of a rotary compressor.

' Figure 2 is a section on the line II--II of Figure 1.

Figure 3 is {a plan view of the valve of Figure 2 with 'the cover omitted.

Figure 4 is a section of a slightly modified form of valve.

Figure 5 is a,plan view of the valve of Fi re 4.

3 shown on the drawings:

A submerged type rotary compressor is artially shown in Figure 1, the outer casing eing indicated by the reference numeral 10 and the outer side wall of the compressor cylinder proper being indicated at 11, the discharge valve of this invention being seated in a recess 12 in said wall and covering the discharge ort 13 leading from adjacent the partition blade of the (pump. The discharge valve recess is covere by a fluid tight cage 14.having an outlet pipe 15 extending above the fluid level in the casing to prevent the compressed gas from bubbling up through the liquid.

One form of this invention comprises a strip type valve spring 16 which normally seals the outlet passage or port 13 and is'secured at one end by a screw 17. The opening movement of the spring strip is limitedby a spaced abutment 18 which normally provides a suficient opening to permit discharge of the compressed gas. However, if liquid has filled the compressor as during a period of idleness, the much larger volume to be discharged necessitates a larger valve opening which vis obtained by leaving the center portion of the spring free to bow outwardly as shown in dotted lines in Figure 2, thus providing much greater discharge areas.

In the modified form shown in Figures 4 and 5 the spring valve strip 16 remains unchanged and is held at one end by the screw 17 substantially as before. The difference resides in the use of a stiffer bent backing spring 19 which forms a normal limiting stop that will yield further when abnormal pressures are developed in the compressor, as when liquid has to be ejected from the compressor at starting. We have found in practice that abnormally high starting torques have been required at times with valve passages which are normally ample for the small volume of compressed gases but which prevent the free exit of liquids.

We are aware that many changes may be made, and numerous details of construction may be varied through a wide'range without departing from the principles of this inven tion, and we therefore do not purpose limitlng' the patent anted hereon, otherwise than necessitated y the prior art.

We claim as our invention: y

1. A discharge valve for rotary compressors comprising a recess in the compressor wall together with a discharge port opening into the bottom of said recess,.a flat valve spring in said recess forming a closure for said port, means securing said spring at one end, a stop normally'determining the opening movement of said. spring, said stop adapted to permit further opening movement of sai spring under abnormal discharge (pressures, a closure for said recess and a s'charge pipe liquid bath surroun ing said compressor.

extending above the 5 2. The combination with a compressor spring adapted to form a limit for the opencylinder having an oblong recess in the outer ing movement of the free end of the spring, a 10 Wall thereof and a discharge port, opening closure sealing said recess and a discharge therein near one end of said recess, of a compipe leading from said closure.

5 pressor discharge valve in said recess com- In testimony whereof, we have hereunto prising a flat spring, means'securing the subscribed our names. spring in said recess at the endopposite the HAROLD W. WISHART.

port, means adjacent the port end of the WILLIAM WISHART. 

